The present invention relates to mining methods, and more particularly, to strip mining methods.
In recent times, strip mine operators have been placed under considerable pressure from two sides. Energy users, on one side, pressure the strip miners to produce more coal, while environmentalists, on the other side, pressure strip miners to leave the environment undamaged. Recently, there have been many moves begun to completely eliminate strip mining unless methods can be devised which leave the mined terrain undamaged and nearly unchanged after completion of a strip mining operation.
Accordingly, strip mining methods must be devised which will satisfy both sides of the strip mining argument. Those strip mining methods must be able to produce large quantities of coal quickly, but must not deface the terrain or mar the beauty of the land.
A further constraint often placed on strip miners arises because a mining lease under which the miners are operating extends for only a short distance. In short leases, economics becomes an important factor. Thus, any new strip mining method should be adaptable to shortwall mining activities, as well as to long unbroken mining leases.
There are several mining methods known. These methods include benches which rotate about a turning-point area in a downwardly spiralling path, and cross-ridge techniques whereby an entire mountain top is ultimately removed.
The known mining methods suffer several drawbacks, among them being the drawbacks caused by the location of the haulage systems in positions which interfere with other machinery used in the operation. Furthermore, the known systems, especially those just-mentioned systems, remove earth in such a manner as to make land reclamation difficult, if not impossible. In fact, the cross-ridge technique, by its very purpose, makes restoring the land to its original layout impossible. The environment, especially that environment affecting wildlife, is therefore severely disrupted by such known techniques.
It is for these reasons, among others, that known strip mining techniques have not met with wide acceptance, either from public groups, or from the strip miners themselves.
The strip mining method embodying the teachings of the present invention solves the above-discussed problems, while providing a mining technique economically adaptable to any terrain layout or mining lease extent. The mining technique embodying the teachings of the present invention should, therefore, find acceptance by both public groups and the strip miners themselves.